Treatment of chlamydial infections: 2014 update

In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level.Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] < 2 μg/ml), intermediate (2 μg/ml ≤ MIC < 4 μg/ml) or resistant (MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment resulted in a greater number of tetracycline resistant isolates.

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“…pneumoniae and C . psittaci are resistant [36, 37]. There are several possibilities to explain the disappearance of resistant C .…”

Section: Discussionmentioning

confidence: 99%

Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs

et al. 2016

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“…More reliable methods to identify chlamydial infections are highlighting that they may be far more prevalent and significant than previously identified [5,6]. Although chlamydial infections within the human population are currently manageable with existing conventional therapies [7,8], chlamydial infections within livestock are of significant concern [6,9].…”

Section: Introductionmentioning

confidence: 99%

Natural Products for the Treatment of Chlamydiaceae Infections

et al. 2016

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Due to the global prevalence of Chlamydiae, exploring studies of diverse antichlamydial compounds is important in the development of effective treatment strategies and global infectious disease management. Chlamydiaceae is the most widely known bacterial family of the Chlamydiae order. Among the species in the family Chlamydiaceae, Chlamydia trachomatis and Chlamydia pneumoniae cause common human diseases, while Chlamydia abortus, Chlamydia psittaci, and Chlamydia suis represent zoonotic threats or are endemic in human food sources. Although chlamydial infections are currently manageable in human populations, chlamydial infections in livestock are endemic and there is significant difficulty achieving effective treatment. To combat the spread of Chlamydiaceae in humans and other hosts, improved methods for treatment and prevention of infection are needed. There exist various studies exploring the potential of natural products for developing new antichlamydial treatment modalities. Polyphenolic compounds can inhibit chlamydial growth by membrane disruption, reestablishment of host cell apoptosis, or improving host immune system detection. Fatty acids, monoglycerides, and lipids can disrupt the cell membranes of infective chlamydial elementary bodies (EBs). Peptides can disrupt the cell membranes of chlamydial EBs, and transferrins can inhibit chlamydial EBs from attachment to and permeation through the membranes of host cells. Cellular metabolites and probiotic bacteria can inhibit chlamydial infection by modulating host immune responses and directly inhibiting chlamydial growth. Finally, early stage clinical trials indicate that polyherbal formulations can be effective in treating chlamydial infections. Herein, we review an important body of literature in the field of antichlamydial research.

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“…Chlamydia trachomatis (0.016-0.064 μg/mL) 40 and Mycoplasma genitalium (0.125-0.25 μg/mL) 41 . This basic modelling approach neglects the changes in volume and biochemistry of vaginal fluid over time (for example, pH), which will influence drug release kinetics and local drug concentration, but it illustrates the potential of these materials for maintaining elevated levels of anti-bacterial concentration and activity over extended periods of time in vaginal fluid.…”

Section: Resultsmentioning

confidence: 99%

“…The controlled delivery of microbicides from IVRs is also advantageous over semi-solid vaginal formulations, for their longer duration, and reduced frequency selfadministration, which increases the adherence of patients to their treatment regimen. IVRs are widely used for contraception (Table 3), with high levels of efficacy and user acceptability 40 . There are very few chances of clinically significant lesions with IVRs and women have a greater preference for IVRs with applicators and a one size fit-free diaphragm for drug delivery 41 .…”

Section: Intravaginal Ringsmentioning

confidence: 99%

“…Therefore the minimum release amount of 5.1 µg/mL/day corresponds to a drug release rate from a PCL IVR of around 18 μg/mL/day. Indeed, in a concurrent PhD project, nevirapine and tenofovir release from PCL matrices and PCL IVRs was directly proportional to PCL length 40 . The predicted concentrations of drug which would be released from a PCL IVR into vaginal fluid are above the minimum inhibitory concentration (MIC) against G. vaginalis (2-12.8 µg/mL) 39 during the study period.…”

Section: Figure 11: Relative Activity (%) Of Metronidazole Released Fmentioning

confidence: 99%

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Controlled delivery of antibacterials using polycaprolactone matrices for the intravaginal treatment of sexually transmitted infections

Pathak¹

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Around 500 million cases of four of the major curable sexually transmitted infections (STIs), Chlamydia, gonorrhoea, syphilis and trichomoniasis, were recorded worldwide in 2008, an increase of 11% from 2005, confirming the need for improved prevention and treatment strategies. The chances of acquiring these infections are 8 times greater in women than men because of biological, social and cultural factors. Furthermore, the presence of these infections increases the chances of both acquisition and transmission of HIV/AIDS by causing genital ulcers and inflammation in the vagina.The human vagina is considered to be a novel, non-invasive and safe route for drug delivery because of its rich blood supply, large surface area and low enzymatic activity.There are many vaginal preparations available in the market but conventional systems such as creams and gels are criticised because of messiness and leakage, and many vaginal formulations have the disadvantage of daily dosing. Intravaginal rings (IVRs) have potential advantages over other delivery systems, in that they can be used for prolonged periods of time, avoid messiness and sustained drug delivery is possible. Previous research has focussed on the use of IVRs for the prevention of HIV. This thesis describes the development of IVRs for the treatment of vaginal bacterial and fungal infections, including STIs.The most important component of IVRs is the polymer used in their construction; currently IVRs are composed of silicone and polyethylene vinyl acetate but these require a high processing temperature and are suitable only for delivery of low molecular weight, hydrophobic drugs. In this thesis, the use of polycaprolactone (PCL) as a potential polymer for use in IVRs is investigated because of its perceived advantages over other polymers, such as low processing temperature and potential to deliver a wide range of drug molecules from hydrophobic to hydrophilic, and low-molecular to high molecular weight.Following a review of the literature in Chapter 1, the delivery of metronidazole using PCL, which could be used for the treatment of bacterial vaginosis, is considered in Chapter 2. Delivery of metronidazole in an IVR could be a better option than the vaginal gel and oral tablet formulations that are currently available because an IVR would provide long term sustained delivery and would be expected to reduce the gastrointestinal side effects associated with oral delivery. PCL matrices loaded with different concentrations of 3 metronidazole achieved an incorporation efficiency of 40-54%. The matrices were studied using a range of approaches including release into simulated vaginal fluid (SVF), morphological and drug distribution studies, thermal characterization and antibacterial activity against Gardnerella vaginalis (one of the main bacteria implicated in bacterial vaginosis). First day burst release occurred due to the presence of drug crystals at the surface of the PCL which was confirmed by scanning electron microscopy and Raman microscopy. Even consider...

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Treatment of chlamydial infections: 2014 update

Cited by 93 publications

References 48 publications

Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs

Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs

Natural Products for the Treatment of Chlamydiaceae Infections

Controlled delivery of antibacterials using polycaprolactone matrices for the intravaginal treatment of sexually transmitted infections

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